Vibrational apparatus

ABSTRACT

Vibrational apparatus capable of providing a vibrational output, said apparatus comprising or including an assembly having a shuttle capable of shuttling between complementary structures, at least one of which complementary structures provides the vibrational output, 
     the arrangement being characterised in that there is a drive to rotate the shuttle and there are magnetic interactions between the rotating shuttle and the complementary structures such that interactions with each complementary structure, and the phasing of the complementary structures relative to the shuttle, alternating magnetic results in the shuttling movement of the shuttle.

The present invention relates to vibrational apparatus.

The present invention relates to vibrational apparatus capable ofproviding a vibrational output for any one of a diverse range ofpurposes (e.g. whether for the purpose of vibrating a drill string, ahopper, a powder feed line, a conveyor, or the like).

Many vibrational apparatus rely upon the rotation of an eccentric.Others rely on pneumatics and/or hydraulics in order to reciprocate apiston which provides a direct output of the vibrational output. Suchstructures however, whilst disclosed for many end uses, have a downsidein that where the device to which the output piston is attached hasitself stalled there is a difficulty in ensuring a recommencement of thevibrational output as a consequence of the piston itself refusing tomove relative to its cylinder or the equivalent.

Vibrational heads whilst disclosed for many end uses, have a downside inthat where the device to which the output piston is attached has itselfstalled there is a difficulty in ensuring a recommencement of thevibrational output as a consequence of the piston itself refusing tomove relative to its cylinder or the equivalent. Such would be the casewith apparatus of PCT/NZ2003/000158 (published as WO 2004/009298) ofBantry Limited.

The present invention recognises a significant advantage from thevibrational commencement point of view and/or tuning point of view(irrespective of how the apparatus is mounted). Can be derived from ashuttle without a direct output to the apparatus to be vibrated.

Irrespective of the apparatus to be vibrated (i.e. whether apparatus inthe form of a drill string or attachment for a drill string or not), werecognise an alternative mode of shuttle reciprocation to that disclosedin the aforementioned specifications. This is preferably one notrequiring a fluid in variable geometry chambers.

We have determined we can provide magnetic interactions at each end of aguided shuttle that, as a result of a rotational drive provided to thereciprocal shuttle, drives such a shuttle back and forth thereby greatlysimplifying operation.

Determined that by providing spaced magnets of a similar polar form andproviding complementary magnets that alternate as to polarity at eachend, it is possible by shuttle rotation to cause reciprocation withoutany striking of solid surface against solid surface. The tuning of thedevice relies on the inherent properties of the magnets involved, thenature of their arrays and the overall geometry of the instruction.Coupled to that there is the fact of the weight of the shuttle itselfand the speed of its rotation.

We believe that permanent magnets can be utilised in such an arrangementeffectively to allow a rotated shuttle to be tuned as far as itsvibrational output is concerned. The timing of transition at each endfrom same pole to same pole to same pole to similar pole interactions issuch as to avoid impact yet nonetheless provided vibrational output fromthe shuttle without any direct connection to any output device.

It is therefore an object of the present invention to provide avibrational head that relies upon rotation of an element of the headthereby to provide magnetic interactions of a different kind (preferablybut not necessarily at each end of a shuttle) thereby to shuttle theshuttle between limits preferably not dictated by any impact orcushioning but preferably rather magnetic to magnetic interactionsdespite any cushioning.

We have also determined it is possible with an air or other floatingbearing or a magnetic levitation bearing to avoid heat build up betweenthe rotating shuttle and the guiding member about which it is to berotatable. Alternatively we have determined that stub axles at each endof a rotatable shuttle can themselves be floated or otherwise supportedin a non-heat build up manner.

It is therefore to some aspects of such construction so the presentinvention is directed together with assemblies, methods of operationsand uses.

The present invention, in some aspects, also recognises at least one ofthe following as desirable irrespective of the form of the vibrationalhead:

an ability to drill to greater depth

an advantage in drill withdrawal

an advantage in drilling restarts

an advantage with vibrational drilling.

The present invention also or alternately sees an advantage in amanoeuvrable support of or frame to compliantly support a vibrationalhead. It is to the vibrational head to which lengths of the drill stringare added. The compliant mounting or support advantageously allows thevibrational head degrees of freedom in movement non destructively of thesupport or frame yet which nonetheless confers (a) a benefit todrilling, an ability to drill to greater depth, a benefit in thesituations of commencement, restart and/or withdrawal and/or (b) abenefit in apparatus longevity and/or simplicity over otherwisesuspended vibrational heads and any attached or to be attached drillstring.

It is to this therefore that the present invention is directed to atleast provide the public with the useful choice.

The present invention consists in vibrational apparatus capable ofproviding a vibrational output, said apparatus comprising or including

a shuttle having first and second ends,

a first complementary structure associating with the first end of saidshuttle, and

a second complementary structure associating with the second end of saidshuttle,

wherein there is a drive or drives to rotate the shuttle about an axisthrough said complementary structures,

and wherein magnets carried by the shuttle at each end and magnetscarried by each complementary structure has the effect such that underthe effect of rotation caused interactions,

the first end moves away from the second complementary structure and, inturn, the second end moves away from the first complementary structure,

and wherein the output of the vibration is from one or other, or both,of said complementary structures and not directly from the shuttleitself.

Preferably said first and second complementary structures are fixedrelative to each other insofar as distance is concerned but not rotationrelative to each other about said axis.

Preferably the drive type for the shuttle in each of its directions isthe same but out of phase, although, in some less preferred forms of thepresent invention, a hybrid arrangement can be used.

Preferably the shuttling is without solid to solid high impact or impactcontact.

Preferably the vibrational output is from one of the complementarystructures.

The present invention also consists in vibrational apparatus capable ofproviding a vibrational output, said apparatus comprising or including

a shuttle able to shuttle reproducibly on a shuttle axis or locusbetween first and second complementary structures,

a drive to rotate the shuttle about at least part of the shuttle axis orlocus, and

magnetic interacting regions on each of at least one complementarystructure and the shuttle whereby rotation of the shuttle has the effectof subjecting the shuttle to shuttle inducing forces being alternatelyattractive and repulsive forces between the or a complementary structureand the shuttle,

and wherein the output of the vibration is from one or other, or both,of said complementary structures and not directly from the shuttleitself.

The present invention also consists in vibrational apparatus capable ofproviding a vibrational output, said apparatus comprising or including

a shuttle rotatable about a defined shuttle axis and moveable back andforth on the shuttle axis,

a drive to rotate the shuttle about its shuttle axis,

a first complementary structure towards which and away from which, andvice versa, the shuttle moves,

a second complementary structure away from which and towards which, andvice versa, the shuttle moves, the shuttle being between saidcomplementary structures,

wherein proximal regions of each pairing of first complementarystructure/shuttle and shuttle/second complementary structure havemagnetic areas operable to provide alternatively for each pairingattractive or repulsive forces as the shuttle rotates,

and wherein the phasing between the pairings is, or can be, such thatthe shuttle reciprocates on its shuttling axis as a consequence of themagnetic interactions that act on the shuttle by virtue of its rotation,

and wherein the vibrational output is from one or other, or both, ofsaid complementary structures and not directly from the shuttle itself.

Preferably said first and second complementary structures are fixedrelative to each other insofar as distance is concerned.

Preferably the shuttling is without solid to solid high impact or impactcontact.

Optionally, but not preferably, said shuttle co-acts at least at one endwith its. complementary structure so as to provide a cushioning affect,e.g. by squeezing a fluid. Alternatively that can be at both ends. Oneor both ends of the shuttle (despite any guiding contact it may alreadyhave) can be adapted to contact part of the complementary structure onlyat the end of its shuttling travel or to contact some materialinterposed between that end of the shuttle and the complementarystructure.

Preferably the vibrational output is from one of the complementarystructures.

In still another aspect the invention consists in vibrational apparatuscapable of providing a vibrational output, said apparatus comprising orincluding an assembly having a shuttle capable of shuttling betweencomplementary structures, at least one of which complementary structuresprovides the vibrational output,

the arrangement being characterised in that there is a drive to rotatethe shuttle and there are magnetic interactions between the rotatingshuttle and the complementary structures such that interactions witheach complementary structure, and the phasing of the complementarystructures relative to the shuttle, alternating magnetic results in theshuttling movement of the shuffle.

Preferably the magnetic interactions are as a result of permanentmagnets.

Preferably the drive of the shuttle is a belt or other peripheral driveof the shuttle not deleterious to the shuttling movement of the shuttlebetween shuttling limits (preferably magnetically defined).

The present invention is directed to alternative vibrational head formsto those disclosed in our PCT/NZ2003/000128 (published as WO2004/113668), and PCT/NZ2005/000047.

The invention also consists in a vibrational head for drilling thatincludes vibrational apparatus as aforesaid. It is also to the use ofdrilling apparatus having a floating or compliant support for avibrational head of the present invention attached to or attachable to adrill string that the present invention is directed.

Preferably at least one, some or all of the following is included;

compliant restriction on one (or both) limit(s) of a or the shuttlestroke

compliant restriction on movement of the vibrational apparatus relativeto its support

compliant bearing of the weight of the vibrational apparatus and anyconnected drill string

a drive to rotate the drill string independently of movement of rotationor lack of rotation of part or all of the vibrational apparatus

a top hat type support assembly to dangle the vibrational head.

In another aspect the invention is a drilling apparatus comprising

a vibrational head of the present invention attached to or attachable toa drill string, a support, and

at least one reconfigurable (e.g. compliant) fluid reservoir (e.g. acompliant gas bag) to carry yet constrain the vibrational head to thesupport,

wherein the interaction of the vibrational head, the support and the atleast one reconfigurable fluid reservoir has the effect of carrying theweight of the attached or the to be attached drill string yet allowingsome freedom of movement of the vibrational head relative to the supportboth longitudinally and laterally of the drill string axis.

Preferably there are at least two reservoirs.

Preferably the fluid in at least one reservoir is a gas (e.g. air).

Preferably at least one, and preferably several or all, of thereservoirs is a gas bag.

Preferably the support is a frame.

Preferably most of the vibrational head (when the drill axis isvertical) is below the reservoir(s).

Preferably the longituding support allows a greater freedom of movementthan the lateral support but not necessarily so.

Preferably irrespective of how the shuttle is caused magnetically toshuttle there is

(a) preferably a vibrational outtake not directly from the shuttle,

(b) the shuttle reciprocates

(c) the shuttle preferably impinges at each end of its stroke on acompliant structure

(d) a or each compliant structure may be a gas bag

(e) the compliant structure(s) preferably can be varied in character toaffect stroke by a variation of a fluid or gas supply

(f) the vibrational outtake is not from a compliant structure but is viaa compliant structure

(g) the shuttle may or may not rotate on its stroke axis.

Preferably the vibrational outtake from the vibrational head into thedrill string is via a transition from a non rotating but vibratingcomponent directly or indirectly into a rotatable and rotating component(e.g. connectable to or forming part of the drill string).

In another aspect the invention is a drilling apparatus comprising

a vibrational head of the present invention attached to or attachable toa drill string, a support,

at least one gas bag interposed between part(s) of the vibrational headand the support, as a first interaction, to carry the weight of thevibrational head and the or any attached drill string, and

at least one gas bag interposed between the support and part(s) of thevibrational head, as a second interaction, to constrain the vibrationalhead relative to the support whereby said first interaction is nottotally lost during any part of the vibrational cycle of the vibrationalhead.

Preferably part(s) of the vibrational head is (are) interposed betweentop and bottom constraints provided by said support and at least one airbag is interposed above the part(s) and below one constraint and atleast one air bag is interposed below the part(s) and above the otherconstraint.

Preferably most of the vibrational head is below said part(s).

The arrangement is such as to provide freedoms of movement of thevibrational head and its carried or to be carried drill string relativeto the support yet able, responsive to weight, to bias to a datumcondition of the vibrational head relative to the support.

In another aspect the invention is a drilling apparatus comprising

a vibrational head attached to or attachable to a drill string, thevibrational head having laterally of the longitudinal axis defined, orto be defined, by the drill string one or more projection(s) to defineat least one upper surface and at least one lower surface,

a support frame for the vibrational head,

at least one gas bag to act between the frame and said at least oneupper surface, and

at least one gas bag to act between the frame and said at least onelower surface.

Preferably the vibrational head has provision both for a compliant (e.g.gas bag or the like) limitation at each end of a shuttle stroke and acompliant (e.g. gas bag or the like) mounting of the vibrational headitself from a support or frame.

Preferably both the upper surface(s) and the lower surface(s) are nearerthe top than the bottom of the vibrational head.

In another aspect the invention is a drilling apparatus comprising

a vibrational head attached to or attachable to a drill string,

a support, and

wherein (I) the vibrational head has a shuttle compliantly restricted inits stroke at least in part by compliant means, and (II) the vibrationalhead is compliantly supported by the support,

and wherein the support via the compliantly supported vibrational headis adapted to carry the weight of the attached or the to be attacheddrill string yet allow some freedom of movement of the vibrational headrelative to the support both longitudinally and laterally of the drillstring axis.

Preferably there are at least two reservoirs of a fluid to provide acompliant support of the vibrational head.

Preferably the fluid in at least one reservoir is a gas (e.g. air).

Preferably at least one, and preferably several or all, of thereservoirs is a gas bag.

Preferably the support is a frame.

Preferably most of the vibrational head (when the drill axis isvertical) is below the reservoir(s).

Preferably the longituding support allows a greater freedom of movementthan the lateral support but not necessarily so.

Preferably the compliant restriction of the shuttle is a reservoir of afluid at an end of the shuttle when at a limit of a stroke.

In another aspect the invention is a drilling apparatus comprising

a vibrational head attached to or attachable to a drill string, the headhaving a rotatably driven shuttle that rotates about is shuttling axisand interacts under rotation with different magnetic effects thereby tobe shuttled, the vibrational output not being from the shuttle itself,

a support,

compliant means (e.g. preferably at least one gas bag interposed betweenpart(s) of the vibrational head and the support), as a firstinteraction, to carry the weight of the vibrational head and the or anyattached drill string, and

compliant means, as a second interaction, (preferably to constrain thevibrational head relative to the support) whereby said first interactionis (preferably) not totally lost during any part of the vibrationalcycle of the vibrational head.

Preferably the vibrational head includes a shuttle compliantlyrestricted as to stroke.

Preferably part(s) of the vibrational head is (are) interposed betweentop and bottom constraints provided by said support and at least one airbag is interposed above the part(s) (e.g. as one option of saidcompliant means) and below one constraint and at least one air bag isinterposed below the part(s) and above the other constraint.

Preferably most of the vibrational head is below said part(s).

Other options exist for the compliant means including a spring, acompressible fluid in a variable volume reservoir, an incompressible orcompressible fluid, or both, in a bag, bellows, or any such variablegeometry containment, resilient or otherwise.

The arrangement is such as to provide freedoms of movement of thevibrational head and its carried or to be carried drill string relativeto the support yet able, responsive to weight, to bias to a datumcondition of the vibrational head relative to the support.

In another aspect the invention is a drilling apparatus comprising

a vibrational head of the present invention attached to or attachable toa drill string, the vibrational head having laterally of thelongitudinal axis defined or to be defined by the drill string one ormore projection(s) to define at least one upper surface and at least onelower surface,

a support frame for the vibrational head,

at least one gas bag to act between the frame and said at least oneupper surface, and

at least one gas bag to act between the frame and said at least onelower surface,

and wherein the vibrational head has a drill string rotational drive toor adjacent its connection for a drill string.

In a particularly preferred embodiment of the present inventionpreferably the apparatus is vibrational drilling apparatus comprising

a vibrational head having a shuttle yet a vibrational outtake notdirectly from the shuttle,

a manoeuvrable support from which the vibrational head is mounted tocompliantly vibrate under the action of the shuttle,

a bearing supported from the vibrational outtake from the vibrationalhead, and a drill string connector carried by the bearing,

a rotational drive to the drill string connector,

wherein the shuttle interacts in use magnetically at each of its ends asit rotates under a drive of the shuttle thereby to reciprocate undereffect of such interactions.

Preferably the rotary drive to the drill string connector is from aflexible transmission from a motor engine or other power source, (e.g.combustive, hydraulic, pneumatic, electric, or the like).

Preferably the flexible drive is of a belt able to provide a rotarytransmission having some capability of reducing transmission of shockfrom the drill string connector to the support yet able to allowvibrational movement of the drill string connector through the bearingfrom the outtake.

The present invention also consists in vibrational apparatus capable ofproviding a vibrational output, said apparatus comprising or including

a shuttle able to shuttle reproducibly on a shuttle axis or locusbetween first and second complementary structures,

a drive to rotate the shuttle about at least part of the shuttle axis orlocus, and

magnetic interacting regions on each of at least one complementarystructure and the shuttle whereby rotation of the shuttle has the effectof subjecting the shuttle to shuttle inducing forces being alternatelyattractive and repulsive forces between the or a complementary structureand the shuttle,

and wherein the output of the vibration is from one or other, or both,of said complementary structures and not directly from the shuttleitself.

Preferably at least one, some or all of the following is included;

compliant restriction on one (or both) limit(s) of a or the shuttlestroke

compliant restriction on movement of the vibrational apparatus relativeto its support

compliant bearing of the weight of the vibrational apparatus and anyconnected drill string

a drive to rotate the drill siring independently of movement of rotationor lack of rotation of part or all of the vibrational apparatus

a top hat type support assembly to dangle the vibrational head.

The present invention also consists in vibrational apparatus capable ofproviding a vibrational output, said apparatus comprising or including

a shuttle rotatable about a defined shuttle axis and moveable back andforth on the shuttle axis,

a drive to rotate the shuttle about its shuttle axis,

a first complementary structure towards which and away from which, andvice versa, the shuttle moves,

a second complementary structure away from which and towards which, andvice versa, the shuttle moves, the shuttle being between saidcomplementary structures,

wherein proximal regions of each pairing of first complementarystructure/shuttle and shuttle/second complementary structure havemagnetic areas operable to provide alternatively for each pairingattractive or repulsive forces as the shuttle rotates,

and wherein the phasing between the pairings is, or can be, such thatthe shuttle reciprocates on its shuttling axis as a consequence of themagnetic interactions that act on the shuttle by virtue of its rotation,

and wherein the vibrational output is from one or other, or both, ofsaid complementary structures and not directly from the shuttle itself.

Preferably at least one, some or all of the following is included;

compliant restriction on one (or both) limit(s) of a or the shuttlestroke

compliant restriction on movement of the vibrational apparatus relativeto its support

compliant bearing of the weight of the vibrational apparatus and anyconnected drill string

a drive to rotate the drill string independently of movement of rotationor lack of rotation of part or all of the vibrational apparatus

a top hat type support assembly to dangle the vibrational head.

Preferably said first and second complementary structures are fixedrelative to each other insofar as distance is concerned.

Preferably the shuttling is without solid to solid high impact or impactcontact.

In still another aspect the invention consists in vibrational apparatuscapable of providing a vibrational output, said apparatus comprising orincluding an assembly having a shuttle capable of shuttling betweencomplementary structures, at least one of which complementary structuresprovides the vibrational output, the arrangement being characterised inthat there is a drive to rotate the shuttle and there are magneticinteractions between the rotating shuttle and the complementarystructures such that interactions with each complementary structure, andthe phasing of the complementary structures relative to the shuttle,alternating magnetic results in the shuttling movement of the shuttle.

Preferably at least one, some or all of the following is included;

compliant restriction on one (or both) limit(s) of a or the shuttlestroke

compliant restriction on movement of the vibrational apparatus relativeto its support

compliant bearing of the weight of the vibrational apparatus and anyconnected drill string

a drive to rotate the drill string independently of movement of rotationor lack of rotation of part or all of the vibrational apparatus

a top hat type support assembly to dangle the vibrational head.

Preferably the magnetic interactions are as a result of permanentmagnets.

Preferably the drive of the shuttle is a belt or other peripheral driveof the shuttle not deleterious to the shuttling movement of the shuttlebetween shuttling limits (preferably magnetically defined).

Optionally there is no reliance upon the provision of an externallypressurised fluid as a means of empowerment of shuttle movement by beingintroduced so as to pressurise without further event between acomplementary structure and said shuttle.

As used herein “shuttle” has the broadest meanings with respect to whatmoves and what does not, etc. Preferably it is a shuttle to moverectilinearly.

As used herein the term “and/or” means “and” or “or”, or, where thecontext allows, both.

As used herein the term “comprises” or “comprising” can mean “includes”or “including”.

As used herein the term “(s)” following a noun can mean both thesingular and plural versions of that noun.

As used herein the terms “stroke” or “stroke limit” can refer to limitsof a rectilinear stroke or any curved stroke (e.g. can swing about apivot axis or other support, whether fixed or moving).

As used herein “compliant” and variations thereof refer to the characterof any structure, whether a gas bag, gas spring or the like, or not,able to achieve a desired stated outcome (e.g. stroke limitation, shockreduction, damping, impact avoidance, etc.).

Optionally there is no reliance upon the provision of an externallypressurised fluid as a means of empowerment of shuttle movement by beingintroduced so as to pressurise without further event between acomplementary structure and said shuttle.

As used herein “and/or” refers to “and” or “or”.

As used. herein “(s)” following a noun can refer to the singular orplural.

Preferred forms of the present invention will now be described withreference to the accompanying drawings in which

FIG. 1 is a diagrammatic view of preferred apparatus in accordance withthe present invention,

FIG. 2 is, a plan diagram of apparatus in accordance with the presentinvention showing a frame having fixed complementary members at each endof a shuttling guide for the shuttle and showing motor drives connectedby belts to rotate the shuttle,

FIG. 3 is a diagrammatic view showing rotation of the shuttle in aclockwise sense between the fixed complementary members and showing with“R” and “A” a circumstance of repulsion and attraction respectivelybetween a complementary component and the shuttle and between theshuttle and the other complementary member such that there is a netshuttling thrust on the shuttle in the arrowed direction,

FIG. 4 shows the arrangement as in FIG. 3 at a moment in time later whenthere is a reversal of the attractive “A” and repulsive “R” forcesbetween the pairings of the fixed complementary component and theshuttle, the shuttle having shuttled in the arrowed direction,

FIG. 5 is a diagram of, for example, the second complementary component,

FIG. 6 is a diagram of each end of the shuttle although it is notnecessary for the polarity of each end of the shuttle to be the same asthe other although this is most preferred,

FIG. 7 is a similar view to that of FIG. 5 but of the firstcomplementary component (e.g. that from which there can be the output)showing in an outer phase condition relative to the component of FIG. 5,the sweep arrow in FIG. 5 showing how provision can be made under theaction of a ram or other external force of rotating one component so asto dame or tune the apparatus as may be required from time to time forservice access or for control of amplitude and frequency,

FIG. 8 shows a drilling head in accordance with the present inventionsuspended so as to carry a vibrating head in accordance with the presentinvention, the vibrating apparatus itself being shown in partialsection,

FIG. 9 shows a suitable assembly procedure for retaining magnets to theshuttle reliant upon a frustoconnical form of the magnets held to theshuttle by a fixed plate,

FIG. 10 is a different embodiment to that of FIG. 10 showing how amachined or moulded frustconnical or other shaped magnet support can befixed into the shuttle in a manner less likely to be subjected todisruption from the shuttling vibration,

FIG. 11 shows part of a preferred maglev bearing shuttle assembly, and

FIG. 12 shows matched (two in this case but could be three or more) beltdrives for the shuttle.

By way of an example one preferred form of the present invention withreference to a drill string vibrating apparatus adapted to attach to adrill string 13.

The apparatus howsoever mounted. (preferably compliantly suspended) hasend members 15 and 16 that act as a first complementary means and 18 and20 which act as a second complementary means. These complementary meansare held in a fixed relationship by the members 19. The shuttle 17 movesback and forward within the physical bounds provided and ideally has alesser shuttling distance to avoid impacting.

It matters not whether or not the shuttle itself acts as a piston withina bore of a complementary end or vice versa. Nor does it matter if thereis no piston in cylinder relationship at all. It is the shuttling thatis important howsoever caused.

With reference to FIG. 1 the following is depicted.

(13) Drill string

(14) Rotary joint/drive pulley

(15) End plate

(16) Adjacent member

(17) Shuttle

(18) Adjacent member

(19) Tie rods

(20) End plate

The purpose of the shuttle 17 is to transfer energy onto the adjacentmembers 16 and 18 in a reciprocal motion. This transfer of energy can beachieved, as in the past, by the injection of oil between the shuttleand its adjacent members with the appropriate timing to cause theshuttle to move in a reciprocal motion, thus to cause the drill stringto move in a linear motion in parallel with the shuttle motion thustransferring the energy down the drill string to the bit in the mostefficient manner. With the present invention however we prefer themagnetic interaction approach to be described hereafter.

The shuttle mass is the key to the transfer of the energy to theadjacent members. The change in direction of travel imparts the energyto the adjacent members. The more mass the shuttle has the greater theenergy required to achieve this change in direction and is directlylinked to the horse power required. The relationship between the mass ofthe shuttle and the total mass of the drill string being vibrated has tobe considered and sized appropriately.

The shuttle action has the advantage of never being in a situation ofbeing stalled by locking or binding of the drill string in the drillhole. The shuttle can deliver full power to the drill string orattachments that may be fitted.

The end plates and tie rods (19, 20) are the link between the adjacentmembers and these transfer the reciprocating energy to the drill string.

The shuttle is preferably reciprocated by magnetic means. Ends of theshuttle have electromagnets or (preferably) rare earth magnets fitted insuch an arrangement that when the shuttle 17 was rotated it would pulseresponsive to adjacent members also fitted with magnets in such a waythat would cause the shuttle to reciprocate. This will be describedhereafter with particular reference to the embodiment of FIGS. 2 to 7.

Hybrids of the foregoing and/or other drives can be used.

The examples above all have a common theme.

(1) The shuttle preferably never needs to touch the adjacent members ina physical sense as this could damage the magnets and the drill stringjoints together with the together with the associated down holeequipment.

(2) The movement of the shuttle preferably is never dependent on thedrill string or attached equipment, being free to move in relation tothe movement of the shuttle.

(3) The shuttle action preferably drives the drill string in bothdirections i.e. in and out and in doing so allows drill bit rotation tomove with very little drag on the drill bit carbides. This action allowsfor back reaming of holes.

Other drill action involving a drifter do not power the drill string outof the hole while drilling the hole “IN”. They rely on the bounce of thedrill string.

A drifter hits steel on steel and in doing so causes a destructive shockwave through the drill string.

N.B. A drifter is the name given to a conventional hydraulic rock drill.

A preferred form of the invention with its magnetic drive will now bedescribed.

FIG. 2 shows the shuttle 1 on a fixed guide shaft 2 supported by theframe 3 which carries the fixed first and second complementarystrictures 4 and 5 respectively.

The power output of the vibration can be from 6 or indeed the end 7 orany other take off linked to the frame 3.

Motors 8 preferably drive belts 9 adapted to rotate the shuttle 1 yetprovide for a limited amount of axial movement of the shuttle as itrotates so as to provide the shuttling effect which gives rise to thevibrational outtake at 6, 7 or via 3.

FIGS. 3 and 4 by reference to regions of different polarity of permanentor other magnets shows the effect. The broken zigzagging arrow isindicative of power take off from a first complementary structure 10. Inthe arrangement shown however there is a second complementary structure11 shown out of phase so far as the “plus” and “minus” polaritiesdepicted are concerned. The shuttle 12 preferably has the same polarityat each end such that, in a condition as shown in FIG. 3, there is a netrepulsive force arising from alignment of “plus” and “plus” polaritiesbetween the shuttle 12 and the first complementary structure 10 whilst,at the same time, there is a “plus” and “minus” attractive force “A”between the shuttle 12 and the second complementary structure 11. Ashort moment in time later the opposite situation, as depicted in FIG.4, exists and it is this rapid alternating of “R” and “A” to “A” and “R”that leads to the reversal in shuttle direction as the shuttle rotates.

In some forms of the present invention, provision is made whereby the180° out of phase situation shown for the complementary structures 10and 11 can be varied and this is shown by reference to a sweep arrow inrespect of FIG. 5. This can be under the action of a ram or other means(not shown) such that during operation the phasing can be moved awayfrom the 180° out of phase situation, or from some other situations, toone that may provide a better tuned frequency of shuttling and amplitudeof shuttling on the shuttle axis.

The outtake of vibration is preferably as shown in FIGS. 3 and 4 via thefirst complementary structure 10.

Even in variations of the invention where there is not the double endedmagnetic interaction described with reference to FIGS. 3 to 7, there cannonetheless be a shuttling effect provided there is an adequate means ofreturn of the shuttle alternatively provided. Examples of such provisionhave been given previously.

Also within the scope of the present invention is the use of themagnetic interactions at or not at the end of the assembly from whichthe vibrational outlook is taken.

It is believed however, that the interactions of the magnet carryingshuttle with a complementary structure will be such as to providedesirable vibrational output useful in drilling and other vibrationaltools. It is seen that the arrangement of the present invention is analternative to, or can be ancillary to other inputs for the end usepurposes, arrangements disclosed in our PCT applicationsPCT/NZ2004/000128 and PCT/NZ2005/000047.

Preferably used are permanent magnets (particularly Rare Earth typemagnets of high magnetic density, e.g. Neodymium magnets, such as thoseof NdFeB, can be stable to 180° C. and Samarium Cobalt magnetic (FmCo)which can be used up to 400° C.).

Other forms of magnet can be utilised including those magnets that maybe developed in the future. Generally speaking however, electro magnetsare contra-indicated purely from the point of view of size and the needto provide adequate electrical inputs in a structure that does vibrateand is subject to adverse environments.

It is envisaged that rotational speeds for the shuttle 1 can varysignificantly. A mere example of one such rotation is 1600 RPM which issufficient, with magnets as depicted, to provide a sufficient throw ofthe shuttle backwards and forwards to provide a worthwhile vibrationaloutput. Usual ranges can be from 1000 to 2000 RPM but can be higher orlower. 2000 RPM equates to approximately 130 Hz.

A different embodiment form of the present invention will now bedescribed by reference to FIG. 8.

In FIG. 8 a main air or fluid (gas) bag group (25) co-acting betweenvibration apparatus part 28 being a fixed or manoeuvrable drill headframe assembly as shown. This assembly provides the drill string (23)with the ability to float in the drill hole while operating regardlessof the weight of the drill string as it is constantly being adjusted byair valves (not shown) to provide equal pressure on the drill stringfixture 32 held between the air bags (25). This assembly also providesthe insulation between the moving mass of the drill string (29) andshuttle assembly and the drill rig structure or support/frame (28).

Those two functions are preferred and can prove to be critical in theoperation of the head.

End plates 27 and 26 (“complementary structures”) are to provide outputto the drill string 23 via shaft 29 and its extension 25. A rotationbearing assembly 24 as a transition allows rotation to the drill string29. Above the bearing assembly 24 the vibrational outtake is independentof drill string rotation i.e. 25 need not rotate. The rotary input tothe drill string spindle below 24 is preferably provided by a wide toothbelt assembly 43 driven by a fixed motor 44. The distance between thedrives is such the movement of the drill string and the associatedvibration is dissipated by the belt drive and therefore is nottransmitted to the drill structure. The belt drive is also such as at tofail owing to the vibration.

Preferably the drive of the shuttle rotation is an electric, pneumaticor hydraulic motor (42) driven flexible drive. Preferably several drivebelts 31 are used. Such belts preferably can accommodate the amplitudesof movement required.

In other drive forms the shuttle can be impelled to rotate reliant onvanes being struck by a fluid (e.g. air, water or the like). Otheroptions for a drive also exist or can be used.

As far as the vibrational apparatus is concerned, it can be seen that anend plate 27 carries an array of magnets 40 to coact with an array ofmagnets 38 at that end of the shuttle 30. Similarly an end plate 26 hascarried magnets 41 as an array to coact with the array of magnets 39held to the shuttle at the other end.

As can be seen, each of the magnets 38 and 39 are shown as preferablyfrustoconnical or shaped forms capable of being held by retention plates36 and 37 to the main body of the shuttle 30.

That main shuttle body preferably is lined with permanent magnets 35 ofa first pole which are to be magnetically levitated about the magneticlining 34 of a second pole of the shaft 29.

Preferably the arrangement is as previously described. If there is adifficulty owing to the intensity of the reciprocation to retain plates36 and 37 to the main body of the shuttle 30, optionally, rather thanthe arrangement as shown in FIG. 9 where magnets 51 are simply held tothe end of the main body 47 by an end plate 48 which can be fixed byadhesion, screwing, bolting or the like (not shown), alternatively, amember 49 can be provided to achieve the same purpose for the magnets 52by screwing radially at 50 into the main body 46 of the shuttle.

Whilst preferably the magnets are exposed at the end of each shuttle, insome instances there can be a protective covering provided that does notinterfere with the effectiveness of the magnetic interaction. Likewisefor the fixed magnets 40 and 41 of the end plates 27 and 26respectively. These can be retained similarly to the shuttle or simpleadhesion may suffice.

It is envisaged that end plate 27 is able to be rotated (e.g. by 45° C.)so that when desired the shuttle 30 can be kept at a stable conditionbetween the end plates 27 and 26 irrespective of whether being rotatedor not. To achieve this the out of phase arrangement previouslydescribed in some detail is used so that there is some balancing of theforces. Just what, if any, rotation of the plate 27 is required dependson the set out of the arrays and the magnetic inclusions in theinteracting surfaces.

The magnetic support of the shuttle on a guiding axis is preferred butin other alternative forms some air or other support can be provided.This is to avoid any unnecessary heat build up which may degrade theperformance of the permanent magnets. Systems in accordance with thepresent invention that have been provided with a lubricated bearing havetended to generate some heat but such systems nonetheless can beoperated if there is cooling of any lubricant or the operatingparameters are such as to not generate temperatures above the degradetemperatures of the permanent magnets.

Also provided is the prospect of a fluid pathway 53 that extends throughthe apparatus into the drill string thus providing a flushing capabilityas well as a prospect of a cooling function. Such a fluid can be air, aliquid (e.g. water) or can include a lubricant fluid typically (e.g. aslurry) used in drilling.

With the arrangement of FIGS. 8 to 12, if for example, the shuttle is1.5 m long and the amplitude of shuttle movement is from 0.1 mm to 15 mm(depending on shuttle rotation speeds, shuttle mass, magnetic arrays,magnetic strengths, geometry and clearances).

Preferably a cycling frequency of from (preferably) above 20 cycle/secto say, 200 cycles/sec are contemplated in steady state conditions. Afrequency 200 cycles/sec can easily be generated using 4/8 magneticinteractions as in FIGS. 2 to 7 reliant on shuttle rotation of about3000 RPM.

1-20. (canceled)
 21. Vibrational apparatus capable of providing a backand forth vibrational output, said apparatus comprising or including ashuttle having first and second ends, a first complementary structureassociating with the first end of said shuttle, and a secondcomplementary structure associating with the second end of said shuttle,wherein there is a mechanical drive or mechanical drives to rotate theshuttle about an axis through said complementary structures, and whereinmagnets carried by the shuttle at each end and magnets carried by eachcomplementary structure has the effect such that, under the effect ofrotation caused interactions, the first end moves away from the secondcomplementary structure and, in turn, the second end moves away from thefirst complementary structure, and wherein the output of the vibrationis from one or other, or both, of said complementary structures and notdirectly from the shuttle itself and is a back and forth output axiallyof, or parallel to, said axis.